The present disclosure relates to anti-ice systems, and more specifically, to anti-ice systems including sensors that sense the presence of ice protection fluid.
Ice buildup on aerodynamic surfaces of aircraft can be problematic. For example, ice can build up on the leading edges of wings and/or engine nacelles. The ice can also disrupt the intended airflow over the aerodynamic surfaces, causing a loss of lift generated by the aerodynamic surface. A combination of design considerations of modern airfoils and modern certification requirements result in less ice tolerance, meaning that modern aircraft need to have more anti-ice capability than some conventional anti-icing technologies can provide. However, existing anti-ice technologies are complicated and/or expensive.
Generally, aircraft with on-board anti-ice or de-ice capability use systems selected from bleed air systems, Tecalemit-Kilfrost-Sheepbridge (TKS) systems or Freezing Point Depressant (FPD) systems, and pneumatic/mechanical boots. FPD systems are considered the most energy efficient, using a glycol-based fluid that is wept onto the leading edge of an airfoil, an engine nacelle, and/or a spinner for a propeller or fan from a porous panel. The glycol-based fluid mixes with water droplets, lowering the freezing point of the water droplets so that the water droplets cannot freeze. The mixture of glycol-based fluid and water droplets then flow off the aircraft together.
Moreover, to verify the FPD system is functioning properly, a pre-flight inspection is performed with the system on. The system is activated and the porous panels are visually inspected to ensure fluid is flowing properly on all of the panels and all the right places. Visual human inspection is time consuming, messy, and difficult since the ice protected surfaces and porous panels are often far away from a mechanic on the ground and commercial aircraft are large. Moreover, commercial aviation ground crews are busy and adding a visual inspection task that entails activating a system in the cockpit is unacceptable.
What is needed, then, is a solution that indicates the functioning of the anti-ice system in a more efficient manner. The present disclosure satisfies this need.